1. Field of the Invention
The present invention relates to measuring and/or inspecting methods, measuring and/or inspecting apparatuses, exposure methods, device manufacturing methods and device manufacturing apparatuses, and more particularly, to a measuring and/or inspecting method in which at least one of a plurality of masks that are placed on an optical path of each of a plurality of exposure lights irradiated to the same area of an area to be exposed on a substrate is measured and/or inspected, an measuring and/or inspecting apparatus that uses the measuring and/or inspecting method, an exposure method in which a plurality of exposure lights are irradiated to an area to be exposed on a substrate, a device manufacturing method that includes an exposure process in which a plurality of exposure lights are irradiated to an area to be exposed on a substrate, and a device manufacturing apparatus that uses the device manufacturing method.
2. Description of the Background Art
Conventionally, from the viewpoint of throughput, the defect inspection of a pattern formation surface of a reticle (mask) is implemented not immediately before exposure, but after reticle manufacturing or at the time of periodic inspection, or the like. However, recently, for the purpose of improving resolution of a device pattern to be transferred on a substrate and the like, a so-called multiple exposure method has been used in which a plurality of patterns are transferred and overlaid to the same area on the surface to be exposed of the substrate (e.g. refer to Kokai (Japanese Unexamined Patent Application Publications) No. 10-209039). In the multiple exposure method, since an effective area size of a pattern to which an exposure light is irradiated is larger, compared with the case of a conventional exposure method, the necessity of defect inspection of the pattern formation surface on a reticle immediately before exposure is increasing.
In the reticle defect inspection immediately before exposure, only the defect that affects the yield of device production is preferably inspected, from the viewpoint of improving the throughput. In the multiple exposure method, however, the exposure result on the substrate is the overlay transfer result of patterns on a plurality of reticles, and therefore, it is extremely difficult to distinguish the defect that is directly related to the yield of device production from other defects on the pattern formation surface, compared with the case of the conventional exposure method.